Ca-Alginate-Carob Galactomannans Beads to Preserve Viability During Digestive Hostility Transit and Cholesterol Uptake Ability of Probiotic Bacteria
Résumé
The assurance of the bacteria survival is the key of the protective technique aiming to alleviate the bacteria resistance under digestive hostilities. Among the methods of protection, microencapsulation of cells in various biomaterials has given convincing results. We tried to exploit for the first time the emulsifying properties of carob galactomannans reinforced herein by the sodium alginate gel in the microencapsulation of beneficial bacteria. On the other hand, we explored the benefits of this protective technique upon the expression of the bacterial ability to uptake cholesterol, in complement to our previously published results. The present study aimed to develop a new mixed gel containing calcium alginate and galactomannans extracted from the Algerian carob seeds endospermes, for the microencapsulation of the human strain of Lactobacillus rhamnosus LbRE-LSAS; compared with the probiotic strain of Bifidobacterium animalis subsp. lactis Bb12. Influence of microencapsulation was tested under simulated digestive environment to verify if both bacteria preserve their viability and their cholesterol assimilation ability. High viable loads of encapsulated LbRE-LSAS and Bb12 were registered (6.97 and 8.66 of 10 Log CFU g −1 , respectively). Conversely, the free cell levels strongly (P < 0.05) decreased during exposure to the digestive simulated conditions. According to our results, the new formed gel permits to improve 1.8-fold on average the cholesterol assimilation ability of probiotic bacteria. We underlined the possible use of carob galactomannans-Ca-alginate beads as alternative healthy solution in protecting beneficial bacteria under gastro-intestinal conditions, and by the way, lowering the serum cholesterol level in the host.